Six Pakistanis and a Syrian man were attacked near Cologne's central train station on Sunday.

Seven migrants were attacked by groups of people in Cologne, Germany on Sunday, 10 January 2016. In picture: Supporters of anti-immigration right-wing movement PEGIDA (Patriotic Europeans Against the Islamisation of the West) carry various versions of the Imperial War Flag (Reichskriegsflagge) during a demonstration march, in reaction to mass assaults on women on New Year's Eve, in Cologne, Germany January 9, 2016.Reuters

Several Pakistanis and at least one Syrian were attacked by groups in Germany's Cologne city, which is already dealing with hundreds of cases of sexual assaults since New Year's Eve.

Six Pakistanis were attacked by at least 20 people near Cologne's central train station on Sunday and a Syrian man was attacked in the same area by five people minutes later, Deutsche Welle reported.

The incidents of sexual assault have raised tensions in Germany, with many blaming German Chancellor Angela Merkel's 'open door' policy that saw more than one million asylum seekers enter the country in 2015.

Many of the woman who complained of being groped and sexually assaulted by large groups of men reportedly told the police that the culprits were 'North African' or 'Middle Eastern' in appearance.

The Cologne police had reportedly received indication that "certain groups would seek to provoke the situation," according to The Local.

The police are reportedly investigating 'grievous bodily harm' in the two attacks on foreigners.

Anti-migrant and racist tensions are likely to rise in Germany, if a rally by anti-immigrant group Pegida in Cologne on Saturday that drew 1,700 people is any indication.

Mass sexual assaults on women were also reported in other German cities on New Year's Eve, prompting German Justice Minister Heiko Maas to suggest that the attacks could have been coordinated.

"Nobody can tell me that this was not coordinated or prepared. There is a suspicion that a particular date was chosen with expected crowds," Mass told German tabloid Bild, according to Deutsche Welle.